Meanwhile, Jon Snow will sing a news report as part of the special broadcast.

On their wedding, Benjamin and Nathan said: "We've been together for nearly 12 years and never thought we'd get the chance to get married for real.

"Doing what we both do for a living has meant that we've spent our entire lives expressing emotion through song, so getting married in a musical, particularly one that we're writing ourselves, felt like the most natural thing in the world."

The musical will also feature performances from the likes of The Feeling, The London Gay Men's Chorus and Sharon D Clarke, as well as messages from Boy George, Will Young, Peter Tatchell, Nick Clegg, Ed Miliband and Lesley Garrett.